Three-dimensional scanning and digitization of the surface geometry of objects is commonly used in many industries and services, and their applications are numerous. The shape of an object is scanned and digitized using a ranging sensor that measures the distance between the sensor and a set of points on the surface. The sensor captures a section of the object's surface from a given viewpoint. To extend the scanned section or to scan the whole surface, the sensor, or the object, is moved to one of several viewpoints and the spatial relationship between all the relative poses between the sensor and the object is obtained. Several approaches exist for measuring and calculating these spatial relationships. One of these approaches exploits targets, such as retro-reflective targets. The system of U.S. Pat. No. 7,912,673 concurrently measures the surface shape of the object after projecting a pattern of structured light while observing retro-reflective targets using at least a pair of cameras. The system builds a model of the surface geometry while it accumulates a model of the 3-D positions of the targets in a single model coordinate system simultaneously. It would be useful to simplify the modeling system to allow operation with a single camera while retaining most functionalities of the full system.